Help! Drivetrain diagnostics.
 

Hi guys,

My car is a 11/2000 4.4i (LH12753)

Was driving on highway when all of a sudden a loud screeching noise starts and car loses power and stops. It doesn't matter which gear (PRNDS) I choose, the screeching continues until the engine chokes and stops turning. Even in neutral. I can start the car again but it will screech badly and motor will choke in 5 seconds or so.


Has anyone heard a similar story before?

This has to be a f$&#'ed tranny, right?

Have you opened up the hood and see if you could isolate the location of the noise? Could be a fan belt that is screeching because of a seized/frozen pulley bearing.

Does the car roll backwards like the gears don't engage? If so, look at the front axle spline.

Otherwise, I would look at a frozen accessory that is making the belt screech as it gets dragged across (alternator, AC compressor, belt tensioner, etc)

Blown trannies tend to be quiet in Neutral. Guess it could be something really bad. Try turning AC off...

Would a seized pulley stop the car from moving? This is a drivetrain issue for sure. When the engine is running it screeches like hell, won't move and engine cannot idle. I'm fearing it's the tranny, I just wanted to ask here if anyone was familiar with the symptoms.

Had identical symptoms on 540i with m62tu engine. The water cooled alternator was the root cause. It has a plastic bushing which centers rear bearing that fell apart causing internal friction and loud noise. I recommend take out serpentine belt and inspect all pulleys / bearings. In my case, alternator caused so much friction that prevented normal idle.